Use inline autocomplete when you already know what to write and only want to type it faster. Good examples include repeated test cases, simple mappings, boilerplate, and a loop whose pattern is clear from nearby code. You can accept only the useful part and keep working without changing focus.
Use chat when the problem needs discussion or extra context. It is better for explaining an error, comparing designs, understanding a library, or planning a change across several files. A useful rule is simple: choose autocomplete when the intent is already clear, and choose chat when you still need to reason about the intent. Chat also works well for safe exploration because its answer does not change project files unless you ask it to.
Rewriting in plainer words…
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